Admittedly, from the Dartford Crossing and north-east London it's six of one and half a dozen of the other between SEN and STN, trunking down the A14 (if they still call it that) from the Midlands and/or the A11 from Narwich, then the M11, then people would be routing past STN to get to SEN.
Take the A12 from north East Anglia and/or from the A14/A45 then they'd never find STN.
